The present invention generally relates to material displacement apparatus and, in a preferred embodiment thereof, more particularly relates to apparatus for releasably coupling a replaceable excavating tooth point or other wear member to an associated adapter nose structure.
A variety of types of material displacement apparatus are provided with replaceable wear portions that are removably carried by larger base structures and come into abrasive, wearing contact with the material being displaced. For example, excavating tooth assemblies provided on digging equipment such as excavating buckets or the like typically comprise a relatively massive adapter portion which is suitably anchored to the forward bucket lip and has a reduced cross-section, forwardly projecting nose portion, and a replaceable tooth point having formed through a rear end thereof a pocket opening that releasably receives the adapter nose. To captively retain the point on the adapter nose, generally aligned transverse openings are formed through these interchangeable elements adjacent the rear end of the point, and a suitable connector structure is driven into and forcibly retained within the aligned openings to releasably anchor the replaceable tooth point on its associated adapter nose portion. A connector structure may also be driven into the aligned openings of other types of telescoped wear and support members such as, for example, an intermediate adapter mounted on the nose of a base adapter.
The connector structure typically has to be forcibly driven into the aligned wear member and support member nose openings using, for example, a sledge hammer. Subsequently, the inserted connector structure has to be forcibly pounded out of the wear member and support member openings to permit the worn wear member to be removed from the support member and replaced. This conventional need to pound in and later pound out the connector structure can easily give rise to a safety hazard for the installing and removing personnel.
This problem is substantially alleviated by the hammerless connector structure illustrated and described in U.S. Pat. No. 6,439,796 to Ruvang et al, assigned to the assignee of the present invention, the disclosure of such patent being hereby incorporated herein by reference. Basically, this hammerless connector structure comprises two longitudinal threaded connector pin sections which are longitudinally inserted toward each other through the wear member and support member connector openings and then threaded together within the interior of the support member opening. Illustratively, the two threaded-together connector pin sections are held in place within the wear member and support member openings by a resilient member compressed between the two connector pin sections or by an internal support member ledge portion interposed between annular ledge portions of the threaded-together connector pin sections. When desired, the inserted connector pin structure may be removed by simply unscrewing the two pin sections from one another and removing them from the wear member and support member openings.
While this design eliminates the need to pound in and then pound out the connector pin structure, it is not operative to compensate for operational surface interface wear between the nose portion of the support member and the wear member which is telescoped onto the nose. Such surface interface wear permits the wear member to move back and forth on the support member nose toward and away from the original installed orientation of the wear member. This, in turn, undesirably accelerates the surface interface wear between the wear member and the support member within the wear member socket area.
In view of the foregoing it can readily be seen that a need exists for a hammerless connector pin structure that is provided with the capability of adjusting for the “loosening” wear between an excavating support member and a wear member telescoped onto the support member. It is to this need that the present invention is primarily directed.